Fraunhofer Institute for Digital Medicine MEVISThe vitality of the liver tissue is an essential parameter for planing as well as for follow-up control of a SIRT therapy. Highly vital liver tissue in one part of the liver might allow a higher dose in the diseased regions since this tissue could compensate adverse effects of the therapy to a greater extend.
Liver specific contrast agents for MRI allow to determine these parameters by using a series of images acquired during the injection. This research area in SIRTOP focuses on the accurate calculation of voxel based dynamic parameters to evaluate the vitality of liver and tumor. Algorithms are developed for motion corrections, the calculation of local longitudinal relaxation times and accurate compensation of MRI field inhomogeneities caused by the B1 effect.
The results of this calibration is the basis for pharmacokinetic models. These are used to create 3D maps of tumor/liver tissue perfusion as well as malignity or vitality of tissue and tumor, respectively. A further alignment of pre and post interventional images allows to determine the success of the SIRT and to look for adverse effects in liver tissue.